I just did a beta 5 build, this has preliminary support for the discussed drag commands (although the GUI editor didn't make it to beta 5).

I'm thinking about calling them "Anchors", any objections?

I unfortunately broke reformatting in beta 4 (and didn't make a fix in beta 5), the problem is that paragraph selection in soft wrap was changed, so it won't find the paragraph automatically (if soft wrap is enabled). Either select it manually or disable soft wrap (cmd-option-w) temporarily. Slightly related is also that when at the begin/end of a paragraph, selecting the paragraph selects too much.

Kind regards Allan